edu.mayo.xsltserver.controller.XsltServerController.java Source code

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/*
 * Copyright: (c) 2004-2011 Mayo Foundation for Medical Education and 
 * Research (MFMER). All rights reserved. MAYO, MAYO CLINIC, and the
 * triple-shield Mayo logo are trademarks and service marks of MFMER.
 *
 * Except as contained in the copyright notice above, or as used to identify 
 * MFMER as the author of this software, the trade names, trademarks, service
 * marks, or product names of the copyright holder shall not be used in
 * advertising, promotion or otherwise in connection with this software without
 * prior written authorization of the copyright holder.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package edu.mayo.xsltserver.controller;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.net.URLConnection;
import java.security.cert.X509Certificate;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Map;

import javax.annotation.Resource;
import javax.net.ssl.HostnameVerifier;
import javax.net.ssl.HttpsURLConnection;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLSession;
import javax.net.ssl.SSLSocketFactory;
import javax.net.ssl.TrustManager;
import javax.net.ssl.X509TrustManager;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.io.IOUtils;
import org.springframework.stereotype.Controller;
import org.springframework.util.StringUtils;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.servlet.ModelAndView;

import edu.mayo.xsltserver.FileService;
import edu.mayo.xsltserver.Transformer;

/**
 * Handles requests for the application home page.
 *
 * @author <a href="mailto:kevin.peterson@mayo.edu">Kevin Peterson</a>
 */
@Controller
public class XsltServerController {

    @Resource
    private Transformer transformer;

    @Resource
    private FileService fileService;

    private SSLSocketFactory sslSocketFactory;

    private final static TrustManager[] TRUST_ALL_CERTS = new TrustManager[] { new X509TrustManager() {

        @Override
        public void checkClientTrusted(X509Certificate[] chain, String authType)
                throws java.security.cert.CertificateException {
        }

        @Override
        public void checkServerTrusted(X509Certificate[] chain, String authType)
                throws java.security.cert.CertificateException {
        }

        @Override
        public X509Certificate[] getAcceptedIssuers() {
            return null;
        }

    } };

    private final static HostnameVerifier VERIFY_ALL_HOST_NAMES = new HostnameVerifier() {

        @Override
        public boolean verify(String arg0, SSLSession arg1) {
            return true;
        }

    };

    public XsltServerController() {
        super();
        try {
            final SSLContext sslContext = SSLContext.getInstance("SSL");
            sslContext.init(null, TRUST_ALL_CERTS, new java.security.SecureRandom());
            // Create an ssl socket factory with our all-trusting manager
            this.sslSocketFactory = sslContext.getSocketFactory();
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    /**
     * Simply selects the home view to render by returning its name.
     *
     * @param request the request
     * @param response the response
     * @param xmlurl the xmlurl
     * @param xmlname the xmlname
     * @param xslturl the xslturl
     * @param xsltname the xsltname
     * @param encoding the encoding
     * @throws IOException Signals that an I/O exception has occurred.
     */
    @RequestMapping(value = "/transform", method = RequestMethod.GET)
    @ResponseBody
    public void transform(HttpServletRequest request, HttpServletResponse response,
            @RequestParam(required = false) URL xmlurl, @RequestParam(required = false) String xmlname,
            @RequestParam(required = false) URL xslturl, @RequestParam(required = false) String xsltname,
            @RequestParam(defaultValue = "application/xml") String encoding) throws IOException {

        Map<String, String> params = new HashMap<String, String>();

        @SuppressWarnings("unchecked")
        Enumeration<String> names = request.getParameterNames();

        while (names.hasMoreElements()) {
            String name = names.nextElement();
            if (name.equals("xmlurl") || name.equals("xmlname") || name.equals("xslturl") || name.equals("xsltname")
                    || name.equals("encoding")) {
                continue;
            } else {
                params.put(name, request.getParameter(name));
            }
        }

        response.setContentType(encoding);

        if (xmlurl != null && StringUtils.hasText(xmlname)) {
            throw new UserInputException("You may specify a 'xslturl' param OR a 'xsltname, but not both");
        }

        if (xslturl != null && StringUtils.hasText(xsltname)) {
            throw new UserInputException("You may specify a 'xmlurl' param OR a 'xmlname, but not both");
        }

        InputStream xsltInputStream;
        if (StringUtils.hasText(xsltname)) {
            File file = fileService.getFile(xsltname);
            if (!file.exists()) {
                throw new UserInputException("The requested XSLT file: " + xsltname + " does not exist.");
            }

            xsltInputStream = new FileInputStream(file);
        } else {
            xsltInputStream = this.createInputStreamFromUrl(xslturl);
        }

        InputStream xmlInputStream;
        if (StringUtils.hasText(xmlname)) {
            File file = fileService.getFile(xmlname);
            if (!file.exists()) {
                throw new UserInputException("The requested XML file: " + xmlname + " does not exist.");
            }

            xmlInputStream = new FileInputStream(file);
        } else {
            xmlInputStream = this.createInputStreamFromUrl(xmlurl);
        }

        transformer.transform(xmlInputStream, xsltInputStream, response.getOutputStream(), params);
    }

    protected InputStream createInputStreamFromUrl(URL url) throws IOException {
        final URLConnection urlCon = url.openConnection();

        if (urlCon instanceof HttpsURLConnection) {
            HttpsURLConnection connection = (HttpsURLConnection) urlCon;
            connection.setHostnameVerifier(VERIFY_ALL_HOST_NAMES);
            connection.setSSLSocketFactory(sslSocketFactory);
        }

        return urlCon.getInputStream();
    }

    /**
     * Handle null pointer exception.
     *
     * @param response the response
     * @param ex the ex
     * @return the model and view
     */
    @ExceptionHandler(UserInputException.class)
    public ModelAndView handleNullPointerException(HttpServletResponse response, UserInputException ex) {

        ModelAndView mav = new ModelAndView("inputError");
        mav.addObject("message", ex.getLocalizedMessage());

        response.setStatus(HttpServletResponse.SC_BAD_REQUEST);

        return mav;
    }

}